In the short story The Case of the Missing Lady, Dr Horriston is a doctor who runs a nursing home located in "The Grange" at the village of Maldon, Sussex.
While investigating the disappearance of Hermione Leigh Gordon, Tommy and Tuppence came across the doctor in the village and suspected that the doctor might be responsible. Their suspicions were increased when they found that the Grange was situated in a remote location, far from prying eyes. Tommy checked with a friend Dr Brady. Brady told him that he knew about Horriston. He called him "a most unscrupulous quack". Horriton had once been a bona fide doctor but had been struck off the register for some reason.
Horriston is described as "a tall dark man with a neat black beard and a powerful unpleasant face."
Portrayals[]
In LWT's 1984 adaptation of the story (Episode 9 of Agatha Christie's Partners in Crime), Dr Horriston is portrayed by Ewan Hooper. Here he has a partner Dr Irma Kleber. In this adaptation, Tuppence already knows about Horriston. Here the misconduct for which he was struck off the register appears to be related to apply armadillo's glands in some treatment. Tuppence has a friend who had a terrible time undergoing one of Horriston's treatments.